Methyl iodide → HCID 15096756, compound

Temperature

60 °C

1-Phenylmethyl-3-hydroxy-4,4-dimethoxypiperidine (3b, 5.5 g, 22 mmol) from Example 1 in 30 ml of dimethylformamide was added slowly to a stirred suspension of sodium hydride (0.81 g, 27 mmol, 80% oil suspension) in 100 ml of dimethylformamide. The reaction mixture was warmed to 60° C. for 2 hours, then cooled to 0° C. whereupon methyl iodide (3.8 g, 27 mmol) was slowly added to the mixture. The reaction mixture was stirred overnight at room temperature then quenched with 10 ml of 10% sodium hydroxide solution. The reaction mixture was concentrated under vacuum, the residue slurried in 300 ml of water and the aqueous mixture extracted with 3×100 ml of ether. The combined organic layers were dried over magnesium sulfate, concentrated under vacuum, then purified by column chromatography (alumina; ethyl acetate/hexane; 2.5:1) to yield the intermediate 1-phenylmethyl-3-methoxy-4,4-dimethoxypiperidine (4b, 3.77 g, 64.6%, Rf 0.63).

1. additionwas slowly added to the mixture
2. customthen quenched with 10 ml of 10% sodium hydroxide solution
3. concentrationThe reaction mixture was concentrated under vacuum
4. extractionthe aqueous mixture extracted with 3×100 ml of ether
5. dry with materialThe combined organic layers were dried over magnesium sulfate
6. concentrationconcentrated under vacuum
7. custompurified by column chromatography (alumina; ethyl acetate/hexane; 2.5:1)

ORD record

ord-fac97ff5c7734040909237f28654ce3d

Source dataset

uspto-grants-1991_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04994471